Stern-Gerlach Experiments on<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>Mn</mml:mi><mml:mo>@</mml:mo><mml:msub><mml:mi>Sn</mml:mi><mml:mn>12</mml:mn></mml:msub></mml:math>: Identification of a Paramagnetic Superatom and Vibrationally Induced Spin Orientation

Rohrmann, Urban; Schäfer, Rolf

doi:10.1103/physrevlett.111.133401

Cited by 54 publications

(60 citation statements)

References 31 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…Therefore, total magnetic moments > 5.0 µ B per atom that have been reported for small iron clusters 167 , and > 3.75 µ B per atom that have been reported for cobalt clusters 45 are in disagreement with our study and seem very unlikely. Consistent with our results and with the observed absence of spatial alignment of the clusters in the ion trap, superparamagnetic behavior 15 of 3d transition metal clusters is also found in Stern-Gerlach experiments on neutral 3d transition metal cluster beams 14,46,169,[172][173][174][175][176][177][178] .…”

Section: F Comparison Of Xmcd Results To Stern-gerlach Experimentssupporting

confidence: 91%

Spin and orbital magnetic moments of size-selected iron, cobalt, and nickel clusters

et al. 2014

View full text Add to dashboard Cite

Spin and orbital magnetic moments of cationic iron, cobalt, and nickel clusters have been determined from x-ray magnetic circular dichroism spectroscopy. In the size regime of n = 10 − 15 atoms, these clusters show strong ferromagnetism with maximized spin magnetic moments of 1 µB per empty 3d state because of completely filled 3d majority spin bands. The only exception is Fewhere an unusually low average spin magnetic moment of 0.73 ± 0.12 µB per unoccupied 3d state is detected; an effect, which is neither observed for Co + 13 nor Ni + 13 . This distinct behavior can be linked to the existence and accessibility of antiferromagnetic, paramagnetic, or nonmagnetic phases in the respective bulk phase diagrams of iron, cobalt, and nickel. Compared to the experimental data, available density functional theory calculations generally seem to underestimate the spin magnetic moments significantly. In all clusters investigated, the orbital magnetic moment is quenched to 5 − 25 % of the atomic value by the reduced symmetry of the crystal field. The magnetic anisotropy energy is well below 65 µeV per atom.

show abstract

Section: F Comparison Of Xmcd Results To Stern-gerlach Experimentssupporting

confidence: 91%

Spin and orbital magnetic moments of size-selected iron, cobalt, and nickel clusters

et al. 2014

View full text Add to dashboard Cite

show abstract

“…Next, we will mainly focus on Mn@Sn 12 and Mn@Ge 12 clusters, based on the magnetic fact that their high magnetic moments were predicted to possess 5 µ B , 4,7,8 respectively. To achieve magnetic superatoms, a singely magnetic TM atom were embedded into a small simple-metal cluster, because either the D-state (magnetic state) of superatoms almost exclusively comes from atomic d-state (that is, for the filling superatomic shells, atomic d electrons are thought as delocalized valence electrons) or its superatomic D-state (magnetic state) hybridize strongly with atomic d-states (that is, atomic d electrons are strongly localized and not fill superatomic shells) in previous reports.…”

Section: Magnetic Analysis and Roles Of Tm's (M's) D Valence Electmentioning

confidence: 99%

“…Such as Mn@Sn 12 cluster with a large spin magnetic moment of 5 µ B , its spin dynamics strongly depends on molecular vibrations and experimental temperatures. 4 Certainly, the fundamental reasons are still because of the change of exchange interaction of electrons and the effect of corresponding ligand field (crystal field) on the change of spin magnetic moment of a cluster. Is there a simple judging method on the change?…”

Section: Magnetic Analysis and Roles Of Tm's (M's) D Valence Electmentioning

confidence: 99%

“…1 Based on the extraordinary stability of superatoms, their optical, dielectric, magnetic, and catalytic properties have been studied in previous reports. 1,3,4 For instance, Zn@Ge 12 and Cd@Sn 12 clusters with a large HOMO-LUMO gap of about 2 eV may be used to assemble optoelectronic materials; 5 accordingly, MnCa n (n=6-15) clusters, 6 Mn@Sn 12 cluster 4,7,8 MnSr 9 cluster, 9 TcMg 8 cluster 10 and V-alkali clusters (VLi 8 , 11 VNa 8 12 and VCs 8 13 ) magnetic superatoms show a large spin magnetic moment of 5 µ B , where the superior stability of Mn@Sn 12 cluster 4,14 was confirmed in experiments. So far, it is generally accepted that the spin magnetic moment of magnetic superatoms is offered by atomic d-state electrons (or superatomic D states) localized on TM sites, while its superatomic stability is provided via the delocalized s, p-valence electrons of metal atoms fully occupied diffuse superatomic S, P states.…”

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

The role of TM’s (M’s) d valence electrons in TM@X12 and M@X12 clusters

2016

View full text Add to dashboard Cite

Using the density functional theory method, the icosahedral TM@X12 (M@X12) clusters (TM=Mn, Tc, Re; M=Zn, Cd, Hg; and X=Sn, Ge), which are composed of Sn12 (Ge12) shell covering a single TM (M) atom, have been systematically examined to explore the role of TM’s (M’s) d valence electrons playing in the clusters. The results show that the magnetism originate from the contribution of TM’s d valence electrons to TM@X12 clusters, where TM’s (M’s) d valence electrons are not included in the superatomic electronic states to TM@X12 (M@X12) clusters. Taking into account the structural stability (imaginary frequency, binding energy, embedding energy, and core-shell interaction) as well as the chemical stability (HOMO-LUMO gap) after, we proposed that TM@X12 and M@X12 clusters can be assigned as the protyle superatoms. Furthermore, the results suggest that M@C60 clusters can not be superatoms, because their negative embedding energies and the distance from the center atom (M) to C atom is larger than the sum of their Van Waals radii. Interestingly enough, we may obtain a simple judging method: for a magnetic superatom, the smaller the energy gap between the highest occupied magnetic state (HOMS) and Fermi level or HOMO (MOgap, or MFgap), the easier on the change of its spin magnetic moment.

show abstract

“…[6] Trotz der einheitlichen Grçße existieren sie in drei verschiedenen magnetischen Zuständen: [15][16][17][18][19][20] [6,11] (extended Xray absorption fine structure) und EPR-Spektroskopie charakterisiert wurden. Details zu den experimentellen Abläu-fen, welche für die Bildung der Cluster in definierter Grçße entscheidend sind, finden sich in der Literatur.…”

Section: Nanopartikelbestehendausmetallischenelementenhabenunclassified

Anomale diamagnetische Suszeptibilität von 13‐atomigen Platin‐Nanocluster‐Superatomen

et al. 2014

View full text Add to dashboard Cite

[1][2][3] was von makroskopischen Pt-Teilchen nicht bekannt ist. Gemäß Vorhersagen werden Metallcluster mit 10 2 -10 3 freien Ladungsträgern supraleitend.[4] Weiter zeigen Pt-Nanopartikel und Pt-Cluster bei tiefen Temperaturen einen ausgeprägten Superparamagnetismus, [5][6][7] während makroskopische Mengen von Pt eine kleine positive magnetische Suszeptibilität aufweisen, welche auf den leicht temperaturabhängingen Pauli-Paramagnetismus zurückgeführt wird. [8] Andere Arbeiten sagen für Metallcluster einen stark erhçh-ten Diamagnetismus vorher, [9,10] Bereits früher haben wir gezeigt, dass in den Poren von NaY-Zeolithen kuboktaedrische oder ikosaedrische Pt-Nanocluster mit einer Grçße von 13 AE 2 Atomen präpariert werden kçnnen.[6] Trotz der einheitlichen Grçße existieren sie in drei verschiedenen magnetischen Zuständen [7] Die Koexistenz verschiedener elektronischer Zustände strukturell nähe-rungsweise identischer Cluster wird auf deren unterschiedliche Umgebung im Zeolithen zurückgeführt, beispielsweise die Gegenwart einer unterschiedlichen Anzahl von AlAtomen im Wirtgitter oder von Na + -oder K + -Ionen in der unmittelbaren Umgebung; aber auch die unterschiedliche Bedeckung mit chemisorbiertem Wasserstoff spielt eine Rolle.Für die vorliegende Studie der magnetischen Eigenschaften wurden diese Cluster in einem speziell eisenfrei hergestellten L-Zeolithen präpariert (Hintergrundinformationen), um jeden Einfluss von Eisenverunreinigungen und darauf beruhende mçgliche Fehlinterpretationen der Daten auszuschließen. Die Kaliumform der Zeolithe wurde durch Rühren in einer 3 mm Lçsung von [Pt(NH 3 ) 4 ]Cl 2 ausgetauscht. Das Produkt wurde gewaschen, getrocknet und unter fließendem Sauerstoff kalziniert, wobei mit 0.5 K min À1 aufgeheizt und die Probe bei der Endtemperatur von 623 K für 5 h belassen wurde. Die Reduktion erfolgte unter einem Fluss von H 2 bei einer Heizrate von 4 K min À1 , wobei die Endtemperatur von 503 K für 1 h beibehalten wurde. Die Struktur des Pt-ausgetauschten Zeolithen wurde mittels Rçntgenbeu-gung (XRD) sowie Festkçrper-NMR-Spektroskopie untersucht (siehe Hintergrundinformationen, Abbildungen S1 und S2), während die Pt-Cluster mittels EXAFS [6,11] (extended Xray absorption fine structure) und EPR-Spektroskopie charakterisiert wurden. Details zu den experimentellen Abläu-fen, welche für die Bildung der Cluster in definierter Grçße entscheidend sind, finden sich in der Literatur.

show abstract

Stern-Gerlach Experiments onMn@Sn12: Identification of a Paramagnetic Superatom and Vibrationally Induced Spin Orientation

Cited by 54 publications

References 31 publications

Spin and orbital magnetic moments of size-selected iron, cobalt, and nickel clusters

Spin and orbital magnetic moments of size-selected iron, cobalt, and nickel clusters

The role of TM’s (M’s) d valence electrons in TM@X12 and M@X12 clusters

Anomale diamagnetische Suszeptibilität von 13‐atomigen Platin‐Nanocluster‐Superatomen

Contact Info

Product

Resources

About